HTTP Header Mangler
HTTP Header Mangler inserts HTTP headers on a per host basis.
HTTP Header Mangler - Firefox Add-on
HTTP Header Mangler is a Firefox add-on which inserts HTTP headers on a per host basis. Matching of hosts is done with either simple strings or regular expressions. Rules can have multiple headers apply to multiple hosts, or simply insert a single header for a single host.
Add-on stats
Weekly download count: 4
Firefox on Android: Yes
Risk impact: High risk impact 
Risk likelihood:
Manifest version: 2
Permissions:
- storage
- webRequest
- webRequestBlocking
- <all_urls>
Size: 11.04K
URLs: Website
Ranking
Other platforms
Not available on Chrome
Not available on Android
Not available on Edge
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Add-on summary
HTTP Header Mangler is a Firefox add-on which inserts HTTP headers on a per host basis.
Matching of hosts is done with either simple strings or regular expressions.
Rules can have multiple headers apply to multiple hosts, or simply insert a single header for a single host.
Example rules:
example.com
.*regexp\d+
# This is a comment.
X-Forwarded-For=10.11.12.13
# Delete headers using "" or ''.
X-Forwarded-For=""
X-Forwarded-For=''
User reviews
I can modify the "Accept" header in outgoing HTTP requests in Firefox 129, so it still works.
It would be nice if syntax errors in the rules would be shown.
by cweiske, 2024-08-27
I must report this dev cuz he is too smart :)))))) i loaded simultaneous heavy sites in 0.4 seconds per total processor time like in the old times ... Beer my friend!!?
I would greatly enjoy a switch-like header on a separate string dedicated to all that burdens loading websites, like java injections, scripts, tags, consent&comply&obey-and-give-me-all-you-have ... And after their site jumped in my Mangler boat to be able to switch and drop case for the second string thus leaving free my highway for just the website
Think about it
Nobody would know who was there or if it was as the request appeared to came from a browser ported on a cloud ... And they record solely the loss of valuable, precious d-a-t-aaa :))) and if lost then nothing happened there
Only their AI bot will enrage its crawling on the cloud for a while, but to find nothing
If this works then I'd be again at surfing speeds we had before the Facebook's wave of sympathy decline started
by AcecardflipsHatsdownmix, 2024-07-27
The idea is great. Produces no effects on Firefox 124. I've tried to remove content-security-policy header with it.
by Vasili Gulevich, 2024-04-05
Add-on safety
Risk impact
HTTP Header Mangler requires some sensitive permissions that could impact your browser and data security. Exercise caution before installing.
Risk likelihood
HTTP Header Mangler is probably trust-worthy. Prefer other publishers if available. Exercise caution when installing this add-on.
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